package cn.bone.kafka.kafka07;

import org.apache.kafka.clients.consumer.ConsumerConfig;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.common.serialization.StringDeserializer;

import java.time.Duration;
import java.util.ArrayList;
import java.util.Properties;

public class CustomConsumerByHandSync {

    public static void main(String[] args) {

        // 0、配置
        Properties properties = new Properties();
        // 连接集群 bootstrap.servers
        properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.1.5:3001,192.168.1.5:3002,192.168.1.5:3003");
        // 反序列化
        properties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
        properties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());

        // 配置消费者组id 名字可以随便取
        properties.put(ConsumerConfig.GROUP_ID_CONFIG, "sui_bian");

        // 设置为手动提交(默认值是自动提交)
        properties.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, false);

        // 1、创建一个消费者
        KafkaConsumer<String, String> kafkaConsumer = new KafkaConsumer<>(properties);

        // 2、订阅主题
        ArrayList<String> topics = new ArrayList<>();
        topics.add("first");
        kafkaConsumer.subscribe(topics);

        // 3、消费数据
        while (true){
            // 每秒拉取一次数据
            ConsumerRecords<String, String> consumerRecords = kafkaConsumer.poll(Duration.ofSeconds(1));
            for(ConsumerRecord<String, String> consumerRecord : consumerRecords){
                System.out.println(consumerRecord);
            }
            // 手动提交offset，实际生产中，使用异步提交的方式较多
            // 同步提交使用 commitSync();
            // 异步提交使用 commitASync();
            kafkaConsumer.commitSync();
        }

    }
}
